The present invention relates to a resaw apparatus and particularly to such apparatus wherein mispositioning and waste of lumber is avoided and wherein sawing equipment is simplified.
In the usual resaw device, a board is conveyed by conveyor means toward a vertical saw where a holdup roll or similar device urges the board sideways against a fixed vertical reference or fence with respect to which the board is sawed. Thus, the fence is the reference with respect to which a saw cut is measured. Generally, the board will be received and conveyed on edge, as when a two-by-four is cut into two one-by-fours.
Unfortunately, since the correct dimensioning of the cut is dependent on the correct positioning and alignment of the board by the holdup roll with respect to the fence, mismanufacture occurs when the board is mispositioned and the holdup roll is unable to align the board on edge in accurate sliding relation to the fence. Furthermore, an accurate holdup roll device represents an expense in addition to the conveyor for moving the boards, the fence against which the boards are positioned, and the vertical saw.
Usually, the holdup roll which urges the board against the fence is spring loaded such that pressure, and therefore accuracy of cut, is somewhat dependent upon the thickness of the board. Moreover, friction and consequent wear on the fence takes place as innumerable boards slide therealong.